January 10, 2010

Happy new year!
A quick mention of our holiday cruise (blog and pictures start here),
an e-mail from Steve Filmer regarding a couple of articles on NPR;
this one on the loudness wars, inluding this great pdf,
and this on one the average level of TV commercials,
a quick mention of James Cameron’s epic, Avatar,
and the final segment (I guess?) on vocal recording, including hung mics and signal structure. I know I’ve covered signal structure in the past, but am having issues finding which episode that was in. If anyone knows off the top of their head, drop me an e-mail, would ya, please? Cheers!

September 13, 2009

This week, Jim Addie hits us with “War and Peace – part 2” on the way dynamic volume adjustments are made on playback in home theatre receivers,
and Ernie asked if I could put together some thoughts on recording and processing the voice, so consider this the first part of a 2 or 3 part series on that.
Jim also provided a link to the Orban processor used for real time loudness adjustment for TV broadcast.

In the last 2 weeks, I’ve recorded several interviews at 2 different trade shows. Those interviews have ended up in episodes of both Shutters Inc and Sine Lanugage.
In the wake of this, I’ve had a couple of enquiries from listeners as to my technique for recording interviews on flash-based field recorders like the Zoom H2.
These listeners have commented that they never seem to achieve the same level of results as I have managed, and have asked for some insights.
So, I shall endeavour to outline the pitfalls as I understand them.

First off, tempting though it may be, do not record to mp3!
Remember, mp3 is a lossy format, and we don’t ever want to save production audio (clips which still need further work before release) in a lossy format.
And for that matter, don’t record at 16 bit wav either.
No, your preferred option is to record 24 bit wav.
Yes, it will chew up your memory cards quicker, but memory cards are really not that expensive these days, so carrying a couple of extras shouldn’t represent too much of a burden, either physically or financially.
If your recorder of choice does not offer 24 bit wav, then fall back to recording 16 bit wav instead.

Secondly, your recorder SHOULD offer a choice of microphone gain sensitivities.
The Zoom H2 offers low, medium and high.
Low will turn the sensitivity down (useful for really loud sources), medium is what it sounds like, and high turns the sensitivity up (for really quiet sound sources).
I have found that the medium setting usually works well for these trade show interviews, but obviously, judge each on a case by case basis.
Remember, we are recording at 24 bit, so we don’t NEED to peg the meters at zero!
Peaks of -20dB to -12dB are just fine!

Third, if your recorder of choice has a headphone output (I don’t imagine there’d be any which do not, but you never know), then absolutely have some form of monitoring with you when you are recording.
This may be a set of lightweight street headphones, or even a decent set of earbuds.
Me? I use my trusty old Sennheiser CX300’s, with just one earbud stuck in one ear.
The reason for that is that through that ear, I can hear what the microphone is picking up, and through my other ear, I’m hearing the world around me.

Now, because you are monitoring (via your earbud) what the microphone of the recorder is hearing, you are able to move the recorder around as necessary througout the interview to make sure the talent stays ‘on mic’.
Now, you might be thinking that people aren’t going to like having a flash recorder stuck in (and moving around in front of) their face.
I would contend that if they have agreed to do an interview, then they are probably going to be ok with it.
My technique is to hold the recorder at chest height between myself and the talent.
That way, you SHOULDN’T get any plosives (pops), but the mic should be able to hear the talent fairly well, while keeping the ambient noise reasonably under control.
If you talent is a very soft speaker, then you may have to move the recorder closer toward them, and that may feel a little uncomfortable at first.
If the talent keeps backing away from the mic, stop the interview, explain to them that you NEED the mic that close in order to hear what they are saying without being drowned by background noise, then recommence the interview.
Thing is, MOST of the time, the person you’ll be interviewing is from the marketing department or the sales team and they generally don’t speak that quietly!!

OK, so now you’re back at your desktop (or in your hotel room working on your laptop) and ready to edit and mix.
Drag the files into your DAW of choice.
DO NOT go and normalise the waveforms!
Remember, they’re 24 bit files, so it’s all good.
In your multitrack (which is also mixing at 24 bits or higher, right? RIGHT??), lay up your interviews where you want them.
Adjust the gain so you’ve got peaks around -20dBFS to -15dBFS off each channel. At this point, you should have NO processing on your master output.
Put in some per channel automation to keep each interview roughly in the bacllpark in terms of output level. You don’t have to get too finicky with it, just ‘in the ballpark’ will be good enough at this stage.
Now, if your final audio piece is going to feature other pieces of audio as well, I’d suggest setting up a submix (buss) for just the interviews to go through.
Then, slap a peak limiter across that buss with an output level set for -15dBFS, and the threshold set so that you’re getting about 4-6dB of gain reduction on that peak limiter.
Then, AFTER the peak limiter, put a compressor with a moderate attack (~20-30ms), moderate release (~100-150ms), a medium ratio (3:1-5:1) and again, enough threshold to give you another 3-6dB of gain reduction.
Your interview submix should now be exhibiting tightly controlled dynmaics, but not sounding squashed.
Go ahead and mix it in with all your other audio bits so that everything sounds roughly equal in apparent volume.
Slap a peak limiter across your master output, and you should be cookin’ with gas!
Have fun!

July 5, 2009

In ep 114, how NOT to attend a trade show,
my man in Hollywood gets back to us on track laying for motion picture,
and JR asked about the best way to record some character interviews outside of the ideal studio environment.

A couple of links for you:

FMR Audio (makers of the RNC compressor)
The Wiki article on dBm,
the Wiki article on decibels,
the Wiki article on Dolby Surround (including info on LtRt), and
the Wiki article on downmixing (which also includes info on LtRt).

November 23, 2008

This week, Greg Anderson sent in a voice comment of his own “radio war story”,
Jim Weishorn wrote to ask for more info on subtractive eq,Alexander Williams* (no relation) wrote to ask about processing audio for live streaming (as opposed to pre-producing content),
…which led me to again remark about having VU meters rather than just peak program meters (PPM’s), and a great free VST plugin VU meter is the Modern Meter,
and then Jim wrote again asking about home theatre… setting up speakers and subwoofers and so on.
After I finished mixing this episode, I realised I didn’t really finish answering Jim’s questions, so consider this ‘part 1 of 2’.
And talk about freaky… in the very week I talk about my Energy 10.2 subwoofer, the damn thing decided to die on me! About an hour after I recorded this ep, I realised that the sub wasn’t working. After some investigating, I came to the conclusion that it had died. I took it to 2 different stores to be checked, and they both deemed that it was dead, too. So, I’m taking it to a friend’s place today for him to have a look at it (he MIGHT be able to fix it). But if he has no luck, looks like I’ll be buying a new sub in the next week or so.

Yes folks.
Believe it or not, we’re finally here!
The building of this video has been an absolute labour of love…. I’d estimate that it’s taken me about 20 hours of work to complete!
Maybe, that’s partly my inexperience at producing video podcasts, but hopefully, when you watch it, you’ll see where those hours went.
In an effort to ease the load on my hosting company’s servers, I will be setting up a torrent feed later tonight.
Check back here later for a link to the torrent file.
There’s also a copy of the file at YouSendIt, plus the copy here at audio2u.com.

If you want to download a copy of the final mix of the song (featuring a couple of extra tweaks I did later), grab that here:Fear of Holding On – 320 kbit joint stereo (13MB)

Towards the end of the podcast (or is that vidcast?), I mentioned that I would make the individual instrument tracks available to anyone who wanted to have a crack at mixing the song for themselves.
Drop me an e-mail and I’ll send you the link to download the files.
Just be warned… that’s an even bigger download than the mp4!!
The tracks are 32bit mono and total about 1.1GB!
The download will be in .rar format, so you’ll need an archive utility like WinRAR (or similar) which is capable of unzipping a .rar file.

March 23, 2008

I know, I know… I told you all that there would be no podcasts for 7 weeks, right?
Yeah well… I got a great e-mail from Meredith Matthews (otherwise known as Mer from Braindouche, but I hadn’t made that connection at the time I recorded this) who asked about the whole “loudness war” thing.
Which of course led me off on a half hour rant about peak limiting, rms, VU, average loudness… all the usual suspects.
Anyway… THIS will be the last podcast for another 6 weeks, ok?
Enjoy.

The prosoundweb thread I mentioned is here.
And here’s some 1kHz tone to play with, if you’re interested.

And a late starter… the ModernMeter plugin can be downloaded from here (right click and “save as”).

February 3, 2008

This week, some e-mail to answer regarding what sampling frequency should we use as a default and why,
utilities to use for ripping and encoding your mp3’s,
how to mix podcasts that prevent your listeners from falling asleep (an area in which I apparently succeed!),
and recording audio on a laptop.
Also, Bruce’s recent home theatre trials and tribulations.

October 14, 2007

This week, I read an absolutely amazing thread on prosoundweb about digital levels.
Some of the ideas fly a little bit in the face of some of the things I’ve suggested in the past (particularly with regard to tracking as hot as possible).
Having now finished reading it (I was still half way through it at the time I recorded this episode), the main gist of what was being discussed (and there were some pretty big industry heavyweights in there) was that if you are tracking in 24 bit, there is no need to aim for the hottest possible level to disc. These guys were advocating tracking with average levels around -20dBFS (and peaks around -12dBFS)! Now, if anyone had tried to sell me on that idea a week ago, I probably would have held on to my existing position and disagreed.
But no, the theory makes a whole lot of sense.
In a nutshell, the idea is this:
At 24 bit resolution, we’ve got 144dB of S/N ratio to play with (or you could refer to it as dynamic range if you wanted to).
NOTHING (Shall I repeat that? NOTHING) that you are going to record into your DAW has that kind of dynamic range.
Nothin’, zip, nada, nil.
For podcasters, the widest dynamic you’re likely to deal with will be your own voice, and even if you’re REALLY inconsistent with levels (and don’t own an outboard compressor), the most you’ll have to contend with might be in the vicinity of 50dB (from the quietest passage to the loudest passage)…. but even that is unlikely.
So, if you track with peaks at -12dB, AND you happen to have a soft passage 50dB below that (-62dBFS), you’ve still got 82dB of S/N below ya!
But why would you need to track that low?
Well, the theory (and according to these heavyweights who are tracking and mixing this way, the practise) suggests that if you track too close to full scale, you might introduce clipping when you start running plugins (EQ, compressors, peak limiters, whatever) that don’t operate at higher bitrates.

Look, it’s not a thread for the faint hearted, but if you have an interest in getting the best possible quality out of your digital audio setup, it’s worth the time and effort.
It took me 4 days to get through it because I kept on re-reading lines and paragraphs to make sure I understood it.
Also, the real meat starts about 7 pages in when Paul Frindle weighs in on the discussion.

OK, enough of that.

This week in the podcast, part 4 in the series on constructing your own promo: some tips on track laying.

September 16, 2007

This week, I received an e-mail from Slau regarding an article he wrote for SoundOnSound magazine back in ’95 regarding digital and analogue levels. It’s definitely worth reading, and you can do so here.

I also had a query from Bruce McKinnon at the Dogbox podcast about convolution reverbs, and how they work.

Plus, the second instalment in the “making a promo for your podcast” series.
This week, the voice over.
Both directing someone else, and doing it yourself.